android.animation

These classes provide functionality for the property animation system, which allows you
to animate object properties of any type. int, float, and hexadecimal
color values are supported by default. You can animate any other type by telling the system how
to calculate the values for that given type with a custom TypeEvaluator.

You can set many different types of interpolators (contained in android.view.animation),
specify keyframes, or group animations to play sequentially
or simultaneously (with AnimatorSet) to further control your animation
behaviors.

Implementors of this interface can set themselves as update listeners
to a TimeAnimator instance to receive callbacks on every animation
frame to receive the total time since the animator started and the delta time
since the last frame.

Implementors of this interface can add themselves as update listeners
to an ValueAnimator instance to receive callbacks on every animation
frame, after the current frame's values have been calculated for that
ValueAnimator.